Changing 20A breakers to 15A breakers requires careful consideration and isn't always a good idea. Here's a breakdown of when it makes sense, when it doesn't, and why

When it might make sense to change from a 20A to a 15A breaker:
The wiring is only rated for 15A

This is the MOST IMPORTANT reason. If the wiring in the circuit is only 14-gauge (AWG), it is only rated for 15 amps. Using a 20A breaker on a 14-gauge wire is a serious fire hazard because it allows more current to flow than the wire is designed to handle, leading to overheating and potentially a fire. This is a code violation.

When it's generally a BAD idea to change from a 20A to a 15A breaker



The wiring is 12-gauge (AWG)

If the wiring is 12-gauge, it is rated for 20 amps. Replacing a 20A breaker with a 15A breaker reduces the capacity of the circuit unnecessarily. You're essentially limiting the amount of power that can be safely drawn from that circuit.

The circuit serves multiple outlets/lights/appliances

20A circuits are often used when the circuit is intended to serve several outlets or power-hungry devices. Downsizing to a 15A breaker could cause nuisance tripping (the breaker trips frequently even under normal use). Think about outlets in a kitchen, garage, or workshop where appliances or power tools might be used.

You don't know the wiring size



If you're unsure of the wire gauge, you MUST determine it before making any changes. You might need to turn off the breaker, remove the outlet or switch plate, and carefully examine the wiring. If you're not comfortable or qualified to do this, hire a licensed electrician.Why leaving the 20A breaker might be better (if the wiring is 12-gauge or larger)



Future-proofing

A 20A circuit provides more capacity for future electrical needs. If you later want to add devices or use more power on that circuit, you'll be better prepared.

Avoiding nuisance tripping

As mentioned earlier, a 15A breaker on a circuit designed for 20A can lead to frequent and annoying tripping.

Code compliance

If the circuit was originally designed and installed with 20A breakers and 12-gauge wire, changing to a 15A breaker might technically be a code violation in some jurisdictions, depending on the specific situation and the intent of the original design.

Key Considerations and Safety



Wiring Size is Paramount

The wire gauge (AWG) determines the maximum safe amperage for a circuit. A 20A breaker must have 12-gauge wire or larger. A 15A breaker can have 14-gauge wire.

Reason for the Change

Why are they making this change? If the 20A breaker is tripping frequently, it's crucial to diagnose the underlying problem rather than just swapping the breaker. The problem could be a short circuit, overloaded circuit, or a faulty appliance. Simply lowering the breaker amperage is a Band-Aid solution that doesn't address the root cause and could create a fire hazard.

Grounding

Ensure the circuit is properly grounded.*

Qualified Electrician



Any electrical work should ideally be performed by a licensed and qualified electrician. They can properly assess the situation, identify any issues, and ensure the work is done safely and according to code. They can also inspect the wiring and determine if it is properly sized for the breaker.

In summary

If the wiring is 14-gauge, changing to a 15A breaker is necessary for safety. If the wiring is 12-gauge or larger, changing to a 15A breaker is generally not a good idea unless there's a specific, valid reason (and even then, it should be done by a qualified electrician after a thorough assessment).

Bottom Line: Safety is the most important consideration. Prioritize using the correct breaker size for the wiring in your home. If in doubt, consult a qualified electrician. They can advise you on the best course of action for your specific situation. Flag for review